Deep-well pump



E. E. JOHNSON DEEP WELL PUMP Oct.l 14, 1930,

Filed Dec. 22, 1927 6 Sheets-Shes?l 1 Oct 14, v1930. E. E. JOHNSON 1,778,453;l

DEEP WELL PUM I Filed Dec. 221927 G sheets-sheet 2 -I /orn egs.

E. E. JOHNSON DEEP WELL PUMP Oct. 14, 1930.

e sheets-sheet s Filed Dec. 22, 1927 n uw I*LO n n s r e n O W@ uw M 78 s 5 Eau zz 2 EB @o Il .d s m e e o8 I4 O m 2 e S. o 2S e i o o@ o B w34 2B oooofwoooooooooo o o\ 3 44 12-9- -v www am.) (.v/ l l rm O O e z 4 s 4. z m n z 7 m 8 www d o v S w `7 F1 OC- 14, 1930 E. E. JOHNSON 1,778,497

DEEP WELL PUMP Filed Dec. 22, 1927 6 Sheets-Sheet 4 Invenor': ETE Johnson. 59% ff To/fn'egs...

14, 1930. E. E. JOHNSQN 1,778,497-- DEEP `WELL. PUMP Filed nec. 22, 1927 e sheets-sheet 5 .Fig-7 In verz-tor: E E Uhnson.

BSM/' www Oct. 1.4, 1930. v E', E, JQHNSQN 1,778,497

DEEP WELL PUMP .Filed Dec. 22, 1927 6 Sheets-Sheet 6 /ft torn eys.

Patented Oct. 14, 1930 EDWARD E JOHNSON, OF ST.IPAUL, MlNNYESOTA Application led December 22, 19.27. Serial No. 241,773.

My invention relates to deep well pumps, and more -particularly to double vstroke geared-pumps having two pump rods for reciprocating two pump plungers in opposite s directions toward andawayfrom each other. The construction disclosed herein is in the nature'of an improvement over my Patent No. 1,438,492 dated December l2, 1922. An object of the present invention is to provide an extremely rigid pump frame or casing in which the operating mechanism is compact-` ly arranged in such manner that the height oi' the pump structurle is reduced to about onehallc of that formerly required. Another object is to provide planetary gear mechanism i-or operating the pump rods so arranged that the pump rods are offset from the center of the planetary gearing whereby the operating mechanism may be brought low down toward Vthe base. -Another object is to provide stuiiing bones which are positioned above instead of at the bottom of the oil reservoir so that the oil which circulates within the pump case can drain back readily and does not subject them to a static head of oil at any time. Another obJectv to pro` vide for-pumping the oil from the oil reservoir to the top ot' the frame or casing and to the planetary gearing from which places it J flows backv to the oil Vreservoir so thatrenewal of oil becomesnecessaryonly at ,long intervals or" time. Another objectistoprovidea pump frame or casing embodying easy means of connecting it'withand disconnecting itv The full objects and advantages-oi' my invention will appear 'in connection with the ydetailed. descriptionthereof, and the novelv particu'- features of my inventive idea will be w larlypointed-out in the claims.

Vtrom operating position.

crank mechanism. Y

In the accompanying drawings which yillustrate a practical embodiment of myV invention, i'

.Fig l is a front elevational view of vthe pump with the cover removed. Figf2 is a view in vertical section as viewedjiirom the front on the line 2-2 ot Fig. 3. Fig. 3 is. a view in vertical section on the lin'e-Jof Fig,2; Fig. 4 is a top plan view of a cross head showing a provision for clearance be# tween the same and a rod carrying membe Fig. 5 is a View in vertical section similar to Fig. 3 showing the pump frame movedback p Fig. 6 is a view in section on the line 6--6 of Fig. 8. Fig. 7 .is a viewin horizontal section. on the line"7-7 of lFig. 2. Fig. 8 is a view in horizontal section on the line 8 8 of Fig. l. lFig. 9 is a view in section on the line 9-9 of'Fig. 8.

As shown in the'dr`awings,l provide aA base member l0 upon which the pump. frame iis adapted to be secured. lThe pump 'frame in- .cludes an oil reservoir at the bottom havingr aA rear wall l2 extending up above the. level of the oil which it is desired to maintain in the reservoir.: The bottom of the .reservoir toward theirontthereof has an inclined 'portion @with a lug 16 provided where'this inclined portion joins the'horizontal portionV ofthe bottom. Y The incline-dportionldv at its upper endmerges into afverticalvwall 18 which is concaved inwardly as shown in Fig'. '7' forithe purpose of providing clearance only as otherwise this wall might j ust as wellbeV iiat. i i The frame has two side members 20 and 22 which entend up urtherthanthe wall 18, these side members being `rounded at their upper ends as will be understood'trom Fig. 3. The lower portions of side members 2O and `22.are provided-withrecessed portions in which internal ring gears'38 are seatedfagainst annular flanges' 25- whichv annular p flangesV merge vvinto vertical wall v18 to complete the oil reservoir infront. Aninular ilanges 25 are provided with clear openingsl 26 through'y which the operating mechanism reciprocates and which willybedescribedjlater. Similar bull' gear housings Aare concentrically'locate'd on the frame by'enclosing'the extended outer rim of ring? gears'- 38-l and are blted'to `side members Cil lil)

2O and 22 by annular langes to complete the oil reservoir, and further as will be apparent from Fig. 9 each bull gear housing has an external bulged portion 29 closed outwardly by cap 140 to enclose and carry the drive shalt 2S and its bearings 133. Side portions 20 and 22 are further provided with clear openings 2T for the assembly and operation of drive shatt- 26 which may be driven in any suitable manner as by means ot a belt pulley 30 secured thereto. Also secured to the shaft 2S are two pinions 32 meshing with external spur gears 34, called bull gears, journalled on studs 36 secured centrally to the bull gear housings 24 by nuts 37. Internal ring gears are rigidly secured in the frame, being concentrically positioned with each other and with the bull gears and located between the latter and the iianges 25. Spur gears 40 mesh with the internal ring gears 38, these spur gears being onehalf of the diameter of the internal gears. A. crank pin 42 has crank members 44 at its two ends and these crank members carry outstanding stub shaft ends 46 which are journalled in the bull 0ears 34 between the centers and periphcries or' the latter. The gears are rigidly mounted on the crank members adjacent the stub shaft ends 46 and are concentric therewith. The crank pin 42 has its axis in the pitch circles of the gears 40. ln the operation of the gearing7 the rotation ot the bull gears carries the gears 40 in an annular path, thereby rolling them around within the internal gears 3S. Since the latter are twice the diameter of the gears 40, the crank pin 42 moves in the path of a diametral line of the internal gears 38 and vertically when as in the present instance, the crank pin and the stub shafts are in a vertical plane at the end ot the stroke. Journaled upon the crank pin 42 is a bearing member 48 or' the vertical connecting rod 50. The connecting rod 50 at its upper end carries a pair for rollers 52 which engage the rear of guideways 54 formed or carried by the inner i'aces of the side members or' the trame 20 and 22 and this connecting rod also at its upper end carries a pair of rollers 56 which engage the front of said guideways. These pairs oi' rollers take care of all horizontal components ot thrusts tending to produce motion and cause the connecting rod 50 to travel straight up and down. Projecting out from the upper end of the connecting rod, there is a lug 38 to which an upwardly extending bolt 60 is adjust-ably secured by nuts 61. An equalizing bar 62 is provided with a central opening through which the bolt passes loosely, the opening, however7 being smaller than the head ot the bolt so that the bar cannot be pulled iree therefrom. Clevises 64 are pivotally attachedto the ends of the bar 62 while ends oi sprocket chains 66 are secured to these clevises. The sprocket chains 66 pass over sprocket Ywheels 68 which revolve on a shaft 7G mounted in the upper portion of the trame. lt is obvious that sprockets 68 serve only to change the direction of the chains 66 and may be replaced by rolls for the same purpose. The other ends ot the sprocket chains 66 are secured to a cross head 72 having a portion to which the upper ends et tie rods 74 are secured by nuts 6. 'lhe lower ends of the rods 74 are secured to a yoke 78 to which is secured the upper end of an outer hollow reciprocating pump rod which slidably surrounds an inner solid reciprocating pump rod 82 whose upper end is secured by a nut 84 to a projection 86 carried by the upper end or the connecting rod 50. The purpose of the bar 62 is to distribute the load on pump rod 8O equal ly between chains 66 irrespective of slight changes in either due to wear, the chain adjustine-nt being maintained by bolt 60. The rod 82 passes through a stuiiing box 8S while the tie rods '74 pass through stutling boxes Q6, these stufiing bez-cs being carried by a bracket 92 whose lower portion is cylindrical to tit oil tight upon a conca-ved cylindrical seat 94 formed in the upper edge ot the wall 18 as will be understood from Fig. 1, this upper edge being thickened to form a flange 96. The portion 93 of the stuiing boi: bracket 92 is in alincment with portions 19 of the pump lrame shown in Fig. 8 to form a continuous abutment within which the lower edge of the sheet metal casing 146 is held to complete the closure ot the pump frame so that oil falling on the casing 146 will drain by gravity onto stui'ling box bracket 92 and from thence down partition 18 to the oil reservoir. The bracket 92 is removably held to its seat by screw bolts 9S for a purpose which will appear later. Retriever chains are secured at one end to the outer end portions of the cross head 72 as shown in Fig. 1 while as shown in Fig. 5, these two retriever chains pass around sprocket wheels 102 carried by the frame and their other ends are secured to pins carried by the upper end ot the connecting rod 56. 1n order to provide a simple and eii'icient means for pumping the oil in the oil reservoir 'for the purpose ot supplying lubrication to the moving parts of the pump, the upper end of a downwardly extending plung er 104 is secured to the lug 56 carried at the upper end ot the connecting rod 50, this plunger reciprocating in a. cylinder 106 whose lower end is anchored to the lug 16 in the bottom ot the oil reservoir. The cylinder 106 is provided with a coupling` member 106 near its lower end and to this coupling member valve casings 110 and 112 are connected at opposite sides thereof as shown in Fig. 2. The valve casing 110 contains a check valve 114 which opens to admit oil into the cylinder when the plunger is moved upwardly. The valve casing 112 contains a check valve 116 which closes when the plunger is moved upwardly. F or downward movement of the plunger, the

'the side walls of the frame.

parts at the top of the frame.

'J fall back into the oil reservoir.

i which rests thereon.

opening and closing of these two'valves are, of course, reversed. The valve casing 112 has connected thereto a vertical pipe 118 to the upper end of which a horizontal pipe section 120 is connected. rl`he outer end of the pipe section 12() is connected to a vertical pipe 122 which continues on to the top of the frame, the purpose of the odset pipe member 120 being to bring the pipe 122 close to one of A horizontal pipe 124 leads from the upper end of the pipe 122 transversely of the frame. The pipe 124 is provided with spraying nozzles 126 for spraying oil upon the guideways and working From the upper part of the pipe member 118, branch pipes 128 and 130 lead into passages 132 as shown in Fig. 6 for lubricating the bearings of the driving shaft and the gearing. The oil after leaving the passages 132 finds its way by gravity to the inside lower portion of the bull gear housing 24 whence it is picked up by the bull gear in its rotation for lubrication thereof and then escapes through the ring gear 38 to Surplus oil traveling along shaft 28 is intercepted by oil groove 135 and returned to the inside of the bull gear housing through the passage 134. ln order to provide a rigid construction for the frame or casing, a flat bar 136 extends between the side members of the frame near their upper ends as shown in Figs 2 and 3. For the same purpose, a curved bar 138 eX- tends between the side members near the position occupied by the-driving shaft 28 as shown in Figs. 4, 5, and 8. The bar 133 is in the form of a half cylinder which when the shaft 28 is in place has an eccentric position in relation thereto. This positioning permits i the shaft 28 and the gears 32 to be introduced place it is permitted to drop so as to bring the teeth of the pinions 32 into mesh with the teeth of the gears 34. vWhen the shaft 28 has been put in place, the bull gear housings 24 are closed by caps 14() which are boltedin place and which contain bearings 135 for the shaft. When the pump is in operating positien, the frame is bolted to the base member 10, which it will be understood from Figs. 5 and 7 is longer than the portion ofthe frame The rear portion of the base on its upper central portion is in the form of a rack having teeth 142. rlhe lower end of the frame carries a perforated lug 144 so that by inserting a pry bar, the frame may be moved backwardly into the position shown in Fig. 5 when itis desired to obtain access to the well and pull the pump rods. By referring to Figs. 1, 3, and 5, it will bef readily understood that the frame may be thus moved backwardly after rst removing thenut84 on the upper end of the pump rod 82, the nuts 76 on the upper ends of the two tie rods 74 and the screw bolts 98` and turning the gearing sufficiently to free the rods from their sockets in the lug 86 and cross head 72 respectively. This may be done without disturbing the operative relation of the parts comprising the dri ving mechanism.

It will be noted from Fig. 3, that there is a slight space betw-een the insideand outside pump rods which may be filled with grease which keeps the rods thoroughly lubricated for a long` time, this grease being kept in place by a stuliing box 150 which'is secured to the upper end of the cutside rod and through which the inside rod passes. The stu-fling box 150 serves also in the usual manner to prevent water leakage. By referring to Fig. 4, it will be seen that the head of the projection 86 carrying the upper end of the inner rod may readily pass the cross head v72 during the up and down strokes. By referring to Fig. 7, it will be understood that the inwardly concaved wall 18 provides clearance for the two pump rods, the yoke 78 and the tie rods 74 so that the pump rods after passing through the base 10 extend up between the space dened by the side walls of the frame as will be apparent from Fig. 3.

By referring aga-in to Fig. 7, it will be noted that sufficient clearance is also left for the up and down movement of the crank pin and the bearing member 48 journaled thereon. It will be seen from 3 that the bearing member 48 at the lower end of the stroke dips into the oil in the oil reservoir and that the wall 18 is in the nature of a partition in the lower portion of the pump casing or chamber and constitutes a confining wall for the oil reservoir.

The entire frame between side portions 20 and 22 above the stuliing box bracket 92 and rear wall 12 is open for the purposes of assembly and inspection in operation if desired and is normally closed by sheet metal cover members 146 and 148 which are adapted to lit inwardly projecting flanges 21 on the side portions 2O and 22 thus completing the enclosingr of the operating mechanism positiened b-etween the side portions of the frame against loss of lubricating oil from within or the entrance of foreign matter from without.

The operation and advantages of my invention have to a large extent been set forth. By means of the planetary gearing and the guide mechanism previously described in detail, the vertical connecting rod 50 is caused to reciprocate straight up and down. Vhen this connecting rod makes its down stroke, :ff

to the upper end ot the hollow pump rod 80, the latter is caused to move upwardly. it the same time, the solid inner pump rod 82 is caused to move downwardly since its upper end is secured to the projection carried by the upper end ot the connecting rod 50. lfilhen the connectimY rod makes its up stroke, the pump rod is caused to move upwardly andthe cross head 72 carrying with it thepump rod 8O is caused to move downwardly by the operation ot the retriever chains l0() connected to said cross head one end and connected at the other end upper end of the connecting rod "O having their direction changed by passing around the sprocket wheels 102. The construction and operation of the pumping mechanism has new been forth wit i sutilcient clearness to allow of a statement ot the improved results secured tliereby compared with my former llnit ,d States latent io. 1,438,492 above relierred to.

The present construction makes possible the following: o con'JY fuct the pump trame with an oil reservoir in the lower portion no pierced by any operating mech: Y which avoids the necessity ot iii:ii"*iiiiir stnitmg' boxes oil tight under a ,f head, to glace the planetary motion and the vert-ical space required for the reciinocation oi'i the or side rod yoke side by side instead oit in anial alinement thus saying head room; to place the pump rod top ends for connection and reciprocation past each other within the same vertical portion of the pump `trame so that the oil stuiiing boxes on 'the rods are above the oil level maintained in the oil reservoir and that their only purpose is to free rods of such oil as splashes on them, there being no stat-iey head of oil to resist; to submerge the lubricating oil pump in the oil reservoir with its plunp n' reciprocated by the pitman in order to provide llood lubrication ot all moving parts; to provide ample openings tor inspection of the pump in operation by the removal ot the sheet metal plates; to provide extreme accessibility to the parts to be separated in moving the pump back to pull the rods from the well; to secure an extremely low center ot gravity ol the trame and operating` parts which adds to their stability and freedom from vilnation in operation.

I claim:

l. In a pump ot the class described, a casing comprising two planetary gear mechanisms in spaced parallel relation, a crank pin connected thereto and reciprocable thereby, a plurality ot pump rods in offset parallel relation thereto, and operating connections between said pump rods and crank pin whereby said pump rods are given motion alternately in opposite and opposed directions in a plane parallel to the plane ot motion of said crank ain.

2. A pump casting comprising an oil reservoir in its lower portion, a detachable stuiiing box bracket carried on one wall thereof above the level of said oil reservoir, a framework comprising` two substantially parallel sides carried thereon, and a sheet metal cover attached thereto to complete the enclosure, substantially and for the purposespecified.

3. A pump comprising a casing, planetary gear mechanism mounted therein, a crank pin connected to said planetary gear mechanism and rcciprocable thereby in a straight line, a pump rod offset with relation to said gear mechanism, and operating connections between said crank pin and said pump rod tor the reciprocation ot the latter in a plane parallel to the plane ot motion or" said crank pin.

el. In a pump, the combination of a frame having seats therein, operating mechanism consisting of a shaft carrying pistons and mounted in said seats in spaced relation and acr a median line ot the Jrame in alinement with each other, said seats being provided with openings oiI sui'icient size to permit assembly of said operating mechanism by endwise sliding movement thereof, a pump rod, and connections between said operating mechanism and pump rod tor reciprocating the latter.

A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, a plurality of pump rods offset with relation to said gear mechanism, and operating connections between said crank pin and said pump rods tor reciprocating the latter in a plane parallel to the plane ot motion of said crank-pin,

6. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, two pump rods oil'set with relation to said gear mechanisni, and operating connections between said crank pin and said pump rods for reciproeating` the latter in opposite direction with relation to each other in a plane parallel to the plane of motion ot said crank pin.

7. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a. straight line, a connecting rod journaled at one end on said crank pin for reciprocation thereby, a projection extending laterallv trom said rod, a pump rod attached to said projection for reciprocating movement, a second pump rod, and operating connections between said connecting` rod and said second pump rod for reciprocating the latter in opposite direction relatively to said first pump rod.

8. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, .a crank pin connected to said planetary Igear mechanism and reciprocable thereby in a straight line, two pump rods offset with relation to said gear mechanism, one of said pump rods being connected with said crank pin in oifset relation for reciprocating movement in the same direction therewith, and connections between said crank pin and the other of said pump rods for reciprocating the latter in opposite-direction Vrela'- tively to said first pump rod in a plane parallel to the plane of motion of said crank pin.

9. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism 'and reciprocable thereby in a straight line, two pump rods offset with relation to said gear mechanism, one of said pump rods being connected with said crank pin in offset relation for reciprocating movement in the same direction therewith, a cross head to which the other of said pump rods is connected, and connections between said crank pin and said cross head for reciprocating the latter in opposite ldirection relatively to said first pump rod in a plane parallel to the plane of motion of said crank pin. s

10. A pump comprising a base, a casing mounted thereon, lplanetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, a connecting rod journaled at one end on said crank pin for reciprocation thereby, a projectionextending laterally from said rod, a pump rodattached to said projection for reciprocating movement, a second pump rod, a cross head to which said second pump rod is connected, operating chains connecting said connecting rod with one side of said cross head, and retriever chains connecting said connecting rod with the other side of said cross head.

11. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in saidcasing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, a connecting rod journaled at one end on said crank pin for reciprocation thereby, guide ways carried'by said casing Yfor-keeping the travel of said rod in a straight line, a projection extending laterally from said rod, a pump rod attached to said projection for reciprocating movement, a second pump rod, and operating connections between said connecting rod and said second pump rod for reciprocating the latter in opposite direction relatively to said first pump rod.

12. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism'and reciprocable `thereby in a straight line, a connecting rod I lsaid connecting rod and one side of said cross head, and laterally deflected retriever chains connecting said connecting rod and the other side of said cross head, said operating and retriever chains being arranged to cause reciprocation of said second pump rod in opposite direction relatively to said first pump rod. y

13. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism andreciprocable thereby in a straight line, a plurality of pump rods otiset with relation to said gear mechanism, operating connections between said crank pin and said pump rods for reciproca*- ing the latter in a plane parallelto the plane of motion of'said crank pin, an oil reservoir below said gear mechanism, and mechanism voperated by said crank pin for delivering oil from said oil reservoir to said gear mechanism and connections'.

lll. A pump comprising a base, a casing mounted thereon, planetary gear mechanism insaid casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, a connecting rod journaled at its lower end on said crank pin, a plurality of pump rods offset with relation to said gear mechanism, operating connections between the upper end of said connecting rod and said pump rods forreciprocating the latter, an oil reservoir below said gear mechanism, a cylinder extending into said oil reservoir and fixed with relation thereto, a plunger attached to the upper end of said connecting rod and working in said cylinder, and pipe connections extending from said cylinder for delivering oil to said gear mechanism and operating connections.

15. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, a plurality of pump rods offset with relation to said gear mechanism, a corresponding number of stufling boxes thereon and through which said pump rods pass` and operating connections between said crank Vpin and said pump rods for reciprocating the latter in a plane parallel to the plane; of motion ofzsaid crank pin.

16. A pump comprising a base, a casingJ mounted thereon, planetarygear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, an oil reservoir below said mechanism, a plurality of pump rods offset with relation to said gear mechanism and oil reservoir, a corresponding number of stuffing boxes above and outside the limits ot said oil reservoir, said pump rods passing through said stutling boxes, and operating connections between said crank pin and said pump rods for reciprocating the latter in a plane parallel to the plane of motion ot said crank pin.

17. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, an oil reservoir below said gear mechanism, an inwardly coneaved partition which constitutes one of the confining walls of said oil reservoir, a plurality of pump rods passing through the space provided by said concaved partition, and operating connections between said crank pin and said pump rods for reciprocating the latter.

18. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, two conccntrically arranged pump rods offset with relation to said gear mechanism, a connection between said crank pin and the inner one of said pump rods for reciprocating the latter in unison therewith, a pair of tie rods connected with the outer pump rod and movable in a common plane with the inner pump rod at opposite sides of the latter, a cross head to which the upper ends of the tie rods are secured, and operating` connections between said crank pin and said cross head for reciprocating the latter in opposition relatively to said inner pump rod in a plane parallel to the plane of motion of said crank pin.

19. A pump comprising a base, a casing mounted thereon, planetary gear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, two concentrically arranged pump rods offset with relation to said gear mechanism, a connection between said crank pin and the inner one of said pump rods for reciprocating the latter in unison with the crank pin, a pair of tie rods connected with the outer pump rod and movable in a common plane with the inner pump rod at opposite sides ot the latter, stuthng boxes supported by said casing and through which said inner pump rod and said tie rods passvrespectively, a cross head to which the upper end of the tie rods are secured, and operating connections between said crank pin and said cross head for reciprocating the latter in opposite direction relatively to said inner pump rod in a plane parallel to the plane of motion of said crank pin.

20. A pump comprising a base, a casing adapted to be slid thereon, means for securing said casing in fixed position on said base, planetary gear mechanism in said casing, a crank pin Connected to said planetary gear mechanism and reciprocable thereby in a straight line, two concentrically arranged pump rods offsetwith relation to said gear mechanism, a detachable connection between said crank pin and the inner one of said pump rods for reciprocating the latter in unison with the crank pin, a pair of tic rods connected with the outer pump rod and movable in a common plane with the inner pump rod at opposite sides of the latter, a block detachably secured to said casing, stuthng boxes carried by said block and through which said inner pump rod and said tie rods pass respectively, a cross head to which the upper ends of the tie rods are detachably secured, and operating connections between said crank pin and said cross head for reciprocating the latter in the opposite direction relatively to said inner pump rod in a plane parallel to the plane of motion of said crank pin.

21. A pump comprising a base, a casing mounted thereon, planetary lgear mechanism in said casing, a crank pin connected to said planetary gear mechanism and reciprocable thereby in a straight line, two concentrically arranged pump rods oiiset with relation to said gear mechanism, a connecting rod journaled at its lower end on said crank pin for reciprocation thereby, a projection eX- tending laterally from said rod and to which the inner one of said pump rods is attached, an equalizer bar attached to the upper end of said journaled rod, a cross head above said pump rods and to which the outer pump rod is attached, two flexible operating members attached respectively to the ends of said equalizer bar and attached to the upper side of said cross head, and two flexible retriever members connecting the lower side of said cross head with the upper end of said journaled rod.

In testimony whereof I hereunto aitix my signature.

EDWARD E. JOHNSON. 

